Digitizer sensors are used as computer input devices for capturing data or handwritten signatures, text, drawings, symbols and the like. Digitizing tablets and touch screens are exemplary digitizer sensors used to replace a mouse as a primary pointing and navigation device for desktop computers. A user interacts with the digitizer sensor by positioning and moving an object such as stylus and/or a finger over a sensing surface of the system, e.g. a tablet and/or a touch screen. Position of the object with respect to the sensor is sensed and interpreted as a user command. A stylus for interacting with the digitizer sensor can be a passive conductive object or a pointing device that transmits a signal.